title: Mannich-Michael versus formal aza-Diels-Alder approaches to piperidine derivatives.
abstract: A review into the aza-Diels-Alder reaction, mainly concentrating on literature examples that form piperidin-4-ones from the reaction of imines and electron rich dienes or enones, either through a Lewis acidic/Brønsted acid approach or through the use of an organocatalyst. This review questions whether the mechanism of the aza-Diels-Alder reaction is step wise as opposed to concerted when using oxygenated dienes.
authors.affiliation: Centre for Sustainable Chemical Processes, Durham University, Department of Chemistry, South Road, Durham, UK DH1 3LE.
authors.forename: P Ricardo
authors.initials: PR
authors.lastname: Girling
authors.forename: Takao
authors.initials: T
authors.lastname: Kiyoi
authors.forename: Andrew
authors.initials: A
authors.lastname: Whiting
mesh_terms: D001372:Aza Compounds / Q000737:chemistry*; D002384:Catalysis; D010084:Oxidation-Reduction; D010880:Piperidines / Q000737:chemistry*; D013237:Stereoisomerism; D013816:Thermodynamics
chemical_list: D001372:Aza Compounds; D010880:Piperidines; C032727:piperidine